/*********************************************************************
This is a library for our Monochrome OLEDs based on SH1106 drivers

  Pick one up today in the adafruit shop!
  ------> http://www.adafruit.com/category/63_98

These displays use SPI to communicate, 4 or 5 pins are required to  
interface

Adafruit invests time and resources providing this open source code, 
please support Adafruit and open-source hardware by purchasing 
products from Adafruit!

Written by Limor Fried/Ladyada  for Adafruit Industries.  
BSD license, check license.txt for more information
All text above, and the splash screen must be included in any redistribution
*********************************************************************/

#if ARDUINO >= 100
 #include <Arduino.h>
 #define WIRE_WRITE Wire.write
#else
 #include <WProgram.h>
  #define WIRE_WRITE Wire.send
#endif

#ifdef __SAM3X8E__
 typedef volatile RwReg PortReg;
 typedef uint32_t PortMask;
#else
  typedef volatile uint8_t PortReg;
  typedef uint8_t PortMask;
#endif

#include <SPI.h>
#include "../Adafruit-GFX-Library/Adafruit_GFX.h"

#define BLACK 0
#define WHITE 1
#define INVERSE 2

#define SH1106_I2C_ADDRESS   0x3C	// 011110+SA0+RW - 0x3C or 0x3D
// Address for 128x32 is 0x3C
// Address for 128x64 is 0x3D (default) or 0x3C (if SA0 is grounded)

/*=========================================================================
    SH1106 Displays
    -----------------------------------------------------------------------
    The driver is used in multiple displays (128x64, 128x32, etc.).
    Select the appropriate display below to create an appropriately
    sized framebuffer, etc.

    SH1106_128_64  128x64 pixel display

    SH1106_128_32  128x32 pixel display

    SH1106_96_16

    -----------------------------------------------------------------------*/
   #define SH1106_128_64
//   #define SH1106_128_32
//   #define SH1106_96_16
/*=========================================================================*/

#if defined SH1106_128_64 && defined SH1106_128_32
  #error "Only one SH1106 display can be specified at once in SH1106.h"
#endif
#if !defined SH1106_128_64 && !defined SH1106_128_32 && !defined SH1106_96_16
  #error "At least one SH1106 display must be specified in SH1106.h"
#endif

#if defined SH1106_128_64
  #define SH1106_LCDWIDTH                  128
  #define SH1106_LCDHEIGHT                 64
#endif
#if defined SH1106_128_32
  #define SH1106_LCDWIDTH                  128
  #define SH1106_LCDHEIGHT                 32
#endif
#if defined SH1106_96_16
  #define SH1106_LCDWIDTH                  96
  #define SH1106_LCDHEIGHT                 16
#endif

#define SH1106_SETCONTRAST 0x81
#define SH1106_DISPLAYALLON_RESUME 0xA4
#define SH1106_DISPLAYALLON 0xA5
#define SH1106_NORMALDISPLAY 0xA6
#define SH1106_INVERTDISPLAY 0xA7
#define SH1106_DISPLAYOFF 0xAE
#define SH1106_DISPLAYON 0xAF

#define SH1106_SETDISPLAYOFFSET 0xD3
#define SH1106_SETCOMPINS 0xDA

#define SH1106_SETVCOMDETECT 0xDB

#define SH1106_SETDISPLAYCLOCKDIV 0xD5
#define SH1106_SETPRECHARGE 0xD9

#define SH1106_SETMULTIPLEX 0xA8

//#define SH1106_SETLOWCOLUMN 0x00 //to use with SSD1306, set to 0x00
#define SH1106_SETLOWCOLUMN 0x02 //to use with SSD1306, set to 0x00
#define SH1106_SETHIGHCOLUMN 0x10

#define SH1106_SETSTARTLINE 0x40

#define SH1106_MEMORYMODE 0x20
#define SH1106_COLUMNADDR 0x21
#define SH1106_PAGEADDR   0x22

#define SH1106_COMSCANINC 0xC0
#define SH1106_COMSCANDEC 0xC8

#define SH1106_SEGREMAP 0xA0

#define SH1106_CHARGEPUMP 0x8D

#define SH1106_EXTERNALVCC 0x1
#define SH1106_SWITCHCAPVCC 0x2

// Scrolling #defines
#define SH1106_ACTIVATE_SCROLL 0x2F
#define SH1106_DEACTIVATE_SCROLL 0x2E
#define SH1106_SET_VERTICAL_SCROLL_AREA 0xA3
#define SH1106_RIGHT_HORIZONTAL_SCROLL 0x26
#define SH1106_LEFT_HORIZONTAL_SCROLL 0x27
#define SH1106_VERTICAL_AND_RIGHT_HORIZONTAL_SCROLL 0x29
#define SH1106_VERTICAL_AND_LEFT_HORIZONTAL_SCROLL 0x2A

class Adafruit_SH1106 : public Adafruit_GFX {
 public:
  Adafruit_SH1106(int8_t SID, int8_t SCLK, int8_t DC, int8_t RST, int8_t CS);
  Adafruit_SH1106(int8_t DC, int8_t RST, int8_t CS);

  Adafruit_SH1106(uint8_t RST);
  Adafruit_SH1106(int8_t SDA=-1, int8_t SCL=-1);

  void begin(uint8_t switchvcc = SH1106_SWITCHCAPVCC, uint8_t i2caddr = SH1106_I2C_ADDRESS, bool reset=true);
  void sh1106_command(uint8_t c);
  void sh1106_data(uint8_t c);

  void clearDisplay(void);
  void invertDisplay(uint8_t i);
  void display();

  void startscrollright(uint8_t start, uint8_t stop);
  void startscrollleft(uint8_t start, uint8_t stop);

  void startscrolldiagright(uint8_t start, uint8_t stop);
  void startscrolldiagleft(uint8_t start, uint8_t stop);
  void stopscroll(void);

  void dim(boolean dim);

  void drawPixel(int16_t x, int16_t y, uint16_t color);

  virtual void drawFastVLine(int16_t x, int16_t y, int16_t h, uint16_t color);
  virtual void drawFastHLine(int16_t x, int16_t y, int16_t w, uint16_t color);

 private:
  int8_t _i2caddr, _vccstate, sid, sclk, dc, cs, sda, scl;
  uint8_t rst;
  void fastSPIwrite(uint8_t c);

  boolean hwSPI;
  #ifndef ESP32
  PortReg *mosiport, *clkport, *csport, *dcport;
  PortMask mosipinmask, clkpinmask, cspinmask, dcpinmask;
  #else
  volatile uint32_t *mosiport, *clkport, *csport, *dcport;
  volatile uint32_t mosipinmask, clkpinmask, cspinmask, dcpinmask;
  #endif

  inline void drawFastVLineInternal(int16_t x, int16_t y, int16_t h, uint16_t color) __attribute__((always_inline));
  inline void drawFastHLineInternal(int16_t x, int16_t y, int16_t w, uint16_t color) __attribute__((always_inline));

};